I often speak with inexperienced email marketers that rail against blacklisting. Many are angry that ISPs have the “right” to divert the commercial electronic messages they send from the inbox, sending them to the junk mail folder or, even more frustrating, to the black hole where email missives go and are never seen again.

Here’s the thing: the more you understand about why blacklists and filters exist, the more you understand that while they’re an obstacle for legitimate email marketers, they are a necessity.

The vast majority of email messages sent are spam. According to Symantec’s latest Intelligence Report, 74.2 percent of all email sent in September and October 2011 was spam. That’s roughly 75 out of every 100 email messages. Symantec is looking at a lot of email – 8 billion messages a day. Yes, you read that right – a day.

You’ll notice that this figure is vastly different from the inbox delivery data provided by Return Path, which I referenced in a column last month. Return Path reports that 81 percent of email sent by legitimate companies makes it to the inbox, with 19 percent being identified as spam and diverted. So what gives?

Return Path is looking at legitimate email – and Symantec is looking at all email. There is a lot of egregious email out there; messages that are sent by people that most of you reading this would agree are spammers. They’re using tactics that legitimate companies would never use – things like transmitting from or relaying email messages through computers that the sender is not authorized to use in an effort to hide their identify.

Imagine if Symantec and every other organization that attempts to identify and filter spam email didn’t exist.

All the legitimate email your company sends would be delivered. That’s good. But so would all the egregious email that is sent. That’s not so good.

Using the Symantec figures, people that receive 26 legitimate messages a day would now receive 100 messages, with 74 of them being egregious spam. Those who are receiving 258 messages a day would suddenly receive 1,000, with 742 of them being spam. Finding legitimate email messages in the inbox, whether it’s a marketing message from a company you trust or a quick note from a friend or family member, would be akin to finding a needle in a haystack. Roughly three of four messages would be egregious spam that would need to be scrolled through and then either ignored or deleted.

And this is a conservative analysis. If companies like Symantec never existed or ceased to exist, then many more spammers would be looking to use this channel. All of our inboxes would soon be overrun with egregious spam, making the channel much less effective than it is, if not completely useless, for any type of commercial or personal communication.

Getting past spam filters to the inbox can be a challenge – but email marketers would face a much different, much more difficult challenge if these filters didn’t exist.

Having your email filtered as spam is akin to getting a speeding or parking ticket; if you’ve been sending email or driving for any period of time, it’s bound to happen. It’s a hassle, no question. But as long as you take action to address the issue and learn from it, you can avoid any long-term negative repercussions. It’s when you avoid dealing with it, either because you’re in denial, unaware, or uncertain what to do, that you put your email program at risk. Seeing spam filters as the “villain” and yourself as an innocent email marketer “victim” isn’t the answer.